The goal of this proposal is to develop and pilot a brief protocol designed to systematically integrate pharmacological interventions for ADHD into behavioral treatment services for adolescent substance users with comorbid ADHD in everyday care. ADHD is a prevalent co-occurring condition for adolescent substance use (ASU) that can significantly impede successful ASU treatment but is vastly under-diagnosed and undertreated among ASU clients in agency settings. Moreover, ADHD medication acceptance and compliance is particularly difficult to achieve in high-risk adolescent populations. The proposed R21 study will use an interrupted time series design to test a brief protocol designed to promote integration of evidence-based ADHD pharmacotherapy into routine behavioral services for ASU: Medication Integration Protocol (MIP). MIP is a 5- session family-based protocol delivered during the early portion of ASU treatment that contains three research- based elements: (1) standardized psychiatric assessment and family-focused psychoeducation about adolescent ADHD; (2) an approved ADHD medication regimen (OROS-MPH) with demonstrated efficacy for ASU/ADHD clients; (3) family-based interventions to support medication acceptance (as indicated) and coordination of care between psychiatric and behavioral services. MIP will be integrated into existing family- based services at one partnering clinical site: 20 ASU/ADHD cases will be treated by site family therapists who will be newly trained and monitored in MIP. The partnering clinic provides family therapy as the routine standard of care for outpatient behavioral health and offers on-site child psychiatry services. Primary study aims will yield proof-of-concept data on MIP feasibility and fidelity in usual care and evidence of MIP impact on psychiatric and behavioral services utilization, medication acceptance and compliance, and satisfaction with treatment services. Exploratory analyses will generate effect sizes for the short-term impact of MIP on the main targets of ADHD medication: ADHD symptoms and executive cognitive functioning. New study products would include a standardized and piloted MIP protocol, clinician training and fidelity monitoring procedures, and an observational fidelity instrument. If validated, MIP could be utilized as a stand-alone intervention in everyday care, or, be combined with existing manualized treatments for ASU in an effort to develop fully integrated treatment models for ASU/ADHD. Also, MIP could be delivered in conjunction with either family- based treatments or individual treatments that can flexibly include caregivers in early sessions.